A variety of techniques are currently available to physicians for controlling elongate medical devices such as catheters, endoscopes and other surgical tools within a patient. For example, magnetic steering techniques provide computer-assisted control of a catheter tip while allowing an operating physician to remain outside the operating room x-ray field. Thus the physician is freed from having to manually steer the catheter tip.
However, the physician still must manually advance the device once the distal end of the device is in the desired orientation. A number of medical procedures call for more than one elongate medical device to be navigated and positioned within a patient's body. For example, during a percutaneous transluminal coronary angioplasty (PTCA), an “over-the-wire” (OTW) procedure may be performed. A guide wire is placed into a lumen of an OTW catheter. The two devices are inserted together and advanced to the procedure site by successively advancing the guidewire guide wire and then the catheter over the guide wire.
In another procedure known as rapid wire exchange (RWE), a guide wire is inserted and navigated to the procedure site. A RWE catheter (also known as a “monorail” catheter) is placed over the proximal end of the guide wire and is advanced over the wire into the patient. The RWE catheter has a short guide wire lumen that is open at both ends, thus facilitating rapid exchange of the catheter with another catheter during the procedure.
It is desirable, of course, to minimize physician fatigue and x-ray exposure during a surgical procedure. Advancing one elongate medical device within and/or next to another elongate device, however, is frequently made difficult by a number of factors, including but not limited to the lengths and frictional characteristics of the devices.